Partic. vol. 15 pp. 18-26 (August 2014)
doi: 10.1016/j.partic.2013.01.004

Solid-state synthesis of Li[Li_0.2Mn_0.56Ni_0.16Co_0.08]O₂ cathode materials for lithium-ion batteries

Wenjuan Hao^a,b, Hanhui Zhan^a, Han Chen^b, Yanhong Wang^b, Qiangqiang Tan^b, Fabing Su^b,*

fbsu@mail.ipe.ac.cn

Abstract

Layered Li[Li_0.2Mn_0.56Ni_0.16Co_0.08]O₂ cathode materials were synthesized via a solid-state reaction for Li-ion batteries, in which lithium hydroxide monohydrate, manganese dioxide, nickel monoxide, and cobalt monoxide were employed as metal precursors. To uncover the relationship between the structure and electrochemical properties of the materials, synthesis conditions such as calcination temperature and time as well as quenching methods were investigated. For the synthesized [Li_0.2Mn_0.56Ni_0.16Co_0.08]O₂ materials, the metal components were found to be in the form of Mn⁴⁺, Ni²⁺, and Co³⁺, and their molar ratio was in good agreement with stoichiometric ratio of 0.56:0.16:0.08. Among them, the one synthesized at 800 °C for 12 h and subsequently quenched in air showed the best electrochemical performances, which had an initial discharge specific capacity and coulombic efficiency of 265.6 mAh/g and 84.0%, respectively, and when cycled at 0.5, 1, and 2 C, the corresponding discharge specific capacities were 237.3, 212.6, and 178.6 mAh/g, respectively. After recovered to 0.1 C rate, the discharge specific capacity became 259.5 mAh/g and the capacity loss was only 2.3% of the initial value at 0.1 C. This work suggests that the solid-state synthesis route is easy for preparing high performance [Li_0.2Mn_0.56Ni_0.16Co_0.08]O₂ cathode materials for Li-ion batteries.

Graphical abstract

Keywords

Lithium-ion batteries; Cathode material; Solid-state synthesis; Lithium-rich material; Electrochemical properties